SERVICE MANUAL CYLINDER HEAD & VALVES Section 3 Figure 29.  - Valve Seat Width g. Correct wide valve seats by grinding top edge of seat with a stone mounted on grinder head.  The stone  must  be  a  smaller  angle  (preferably  1  5 degrees) than the valve seat. NOTE:        If    valve    does    not    seat    properly    after resurfacing valve seats, replace valve seats. 6. Replace valve seat as follows: a. Remove  valve  seats  with  a  slide  hammer and  expanding  screw  with  pre-cup  puller. Two     pre-cup     pullers     are     available     for service   one   for   intake,   one   for   exhaust valves.  (See Tool List for tool numbers). b. Clean    counterbore    (in    head),    to    assure proper   valve   seat   mating   and   good   heat transfer. c. If  right  fit  is  NOT  assured  between  mating surfaces  of  valve   seat   and   cylinder   head counterbore,    install    oversize    valve    seat inserts as follows: 1. Take  a  light  cut  from  bottom  of  insert counterbore in cylinder head to dimensions   shown   in   the   valve   seat insert chart for correct fit. 2. Maintain  radii  shown  in  Fig.  30  when enlarging     counterbore     for     oversize inserts. VALVE SEAT INSERT CHART (OVERSIZE) DIAMETER OF CYLINDER HEAD COUNTERBORE* Oversize Engine Insert Intake Exhaust Naturally Aspirated 002 in None 38.96-38.99 mm (1.534-1.535 in) 312 and 360 **.005 in None 3904-39.07 mm (1 537-1.538 in) 015 in None 39.29-39 32 mm (1.547-1.548 in) .002 in 45.19-45.21 mm (1.779-1.780 in) 38.96-38.99 mm (1.534-1.535 in) Turbocharged 360 **.005 In 45.26-45.29 mm (1.782-1.783 in) 39.04-39.07 mm (1 537-1.538 in) .015 in 45.52-45.54 mm (1.792-1.793 in) 39.29-39.32 mm (1.547-1 548 in) All 414, .002 in 50.75-50.77 mm (1.998-1.999 in) 41.30-41.33 mm (1.626-1.627 in) 436 and 466 **.005 in 50.83-50.85 mm (2.001-2.002 in) 41.38-41 40 mm (1.629-1.630 in) .015 in 51.08-51 10 mm (2.011-2.012 in) 41.63-41.66 mm (1.639-1.640 in) *It is not necessary to enlarge the Insert counterbore before Installing the standard size Insert. ** .005 Inch oversize Insert is no longer available for service. CGES-185-3 PRINTED IN UNITED STATES OF AMERICA Page 23